Project A5

Piezotronic Magnetoelectric Sensors

Project A5 employs piezotronics for improving the ME sensors. Preliminary work shows the suitability of various ME sensor types for the piezotronic concept, including ZnO, AlN, and PZT. The well-known piezotronic material from literature, ZnO, will be utilized to investigate the effect of morphology, doping, defects, crystal quality, interfaces, as well as the local stress distribution behavior. Using FFT impedance spectroscopy, will help with understanding the details of the electrical and electronic properties in the Schottky and ohmic contacts. Besides fundamental understanding of piezotronics for ME sensors, an increase in the limit of detection (LoD) by three orders of magnitude is expected as indicated by preliminary work..

Role within the Collaborative Research Centre

In principle, the piezotronic approach is transferable to many different sensor types. This potential will be elucidated with the other groups listed below. Due to the difference in noise sources and sensor layout, further modeling and characterization in conjunction with other groups is required. Especially the ZnO model system makes a detailed understanding of the role of defects and stress distribution on the piezotronic features possible and will be explored in operando in TEM and synchrotron x-ray experiments to gain fundamental understanding of underlying principles. The impedance spectroscopy will be provided as a service to all projects that need a specification of dielectric films.

The characterization of the in situ micro-structural changes will be performed in close collaboration with TEM and synchrotron x-ray experiments. Push-to-pull devices will be customized to enable the measurement of strained piezoelectric materials in TEM and synchrotron x-ray analyses.